1. Field of the Invention
The present invention relates to frames for glasses and, more particularly, to an adjustable nose-rest mechanism and a detachable clip-on nose-rest mechanism for bi-focals that allows ready one-hand adjustment of the nose rest elevation relative to the lenses in order to vertically position the lenses (rather than tilting of the head) for ease of viewing computer screens, television screens, top shelves, and the like.
2. Description of the Background
Most wearers of bi-focals will readily appreciate the propensity for neck strain caused by prolonged use. The lenses of the bifocals are typically formed such that the wearer looks downwardly through the lenses when reading or otherwise viewing through the near vision part of the lenses, and looks straight ahead or upwardly when using the distant part of the lenses. However, very frequently the wearer may desire to use the lower or near vision section of the lens parts while looking straight ahead. This is often the case when trying to view a computer or television screen, or top shelves. To focus on the screen using the near vision part of the lenses, the wearer must tilt his/her head backward by approximately 40 degrees. When typing from a flat-lying paper document, the neck-tilting process must be repeated countless times in succession. Conversely, there is often a need to use the upper or far vision section of the lenses while looking straight ahead. For example, this may be necessary when viewing a television from a reclining position. To focus on the TV screen using the far vision part of the lenses, the wearer must tilt their head forward by approximately 40 degrees. In either of the above-described situations the net long-term result is often neck strain.
There are an abundance of prior devices that attempt to position the spectacles by raising or vertically elevating the lenses. Generally, these examples do not allow for both elevating and/or lowering the lenses through a full range. In addition, many of the prior art devices are overly complex, either structurally in the manner by which they are attached to the bi-focals, or functionally as to the manner by which they are adjusted.
For example, U.S. Pat. No. 3,365,263 to Allen shows an unwieldy inflatable nose pad for raising and lowering spectacle frames. The user carries a small hand pump.
U.S. Pat. No. 6,045,223 to Kawabata shows an extremely complicated nose pad adjustment device in which the nose pad is mounted on a bracket that adjustably slides through a yoke. The bracket may be moved to one of an upper location or lower location to adjust the vertical offset of the lenses.
U.S. Pat. No. 4,280,758 to Flader et al. shows adjustable bi-focals with a spring-biased slider element that can be moved up or down and locked into position by a latch. While the Flader et al. concept is very functional and can be adjusted simply by pressing the frame downward against the nose with one hand, the mechanism (inclusive of springs and star-wheel latch) is fairly complex and difficult to manufacture.
It would be greatly advantageous to provide an adjustable nose-rest mechanism for bi-focals that allows ready one-hand adjustment of the near-vision portion of the lens in order to vertically position the lenses (rather than tilting of the head) for ease of viewing through the lower or near vision section of the lens parts while looking straight ahead (such as when viewing above-reading-level objects like shelves, etc.), or for viewing through the far vision section of the lens (such as when viewing below reading-level objects or when viewing from a reclining position). It would further be advantageous to provide a detachable clip-on nose-rest mechanism for bi-focals that adjusts the nose rest relative to the near-vision portion of the lens.
It is, therefore, an object of the present invention to provide an adjustment mechanism for the nose-rest of bi-focals that facilitates easy one-hand adjustment of the elevation of the lenses.
It is another object to provided a simpler alternative way of vertically locating bi-focal lenses (rather than tilting the head) to alleviate neck strain when viewing computer and television screens, and top shelves in libraries and stores.
It is still another object to provide a mechanism as described above that allows adjustment along a continuous and broad range of elevations, and which securely locks the nose rest in place at any location there along.
It is still another object to provide a mechanism as described above that can clip on to any standard pair of bi-focal glasses and be easily detached from the bi-focals when not needed.
It is yet another object to provide a mechanism as described above that can be easily adjusted to fit any pair of standard bi-focals.
It is another object to provide a mechanism as described above that is rugged, stable, and yet economical to manufacture.
It is still another object to provide a mechanism as described above that has aesthetic value.
According to the present invention, the above-described and other objects are accomplished by providing an apparatus for adjusting the height of bi-focals relative to the user""s eyes. The apparatus generally includes a boss secured to said bi-focals, said boss comprising a hollow sleeve aligned vertically, or individual guides attached to the brow bar and the nose bridge. An elongate slider is slidably carried in the boss or guides, and a nose rest is attached at the lower end of the slider. A set screw having an elongated head (for two-finger turning) is threaded frontally into the boss or eyeglass frame bar and is tightenable against the slider. Given the foregoing configuration, the nose rest can be adjusted along a continuous range of elevations and locked into any of said locations by tightening the set screw, thereby facilitating one-hand adjustment of the lens elevation and the detachable nose-rest mechanism can be temporarily attached to compatibly designed bi-focal glasses for viewing through the alternate location of the lens, thereby facilitating vertical positioning of the lens with simple attachment and detachment of the nose-rest assembly.